JPS6295940A - Non-interruption electric source - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an uninterruptible power supply device that switches between a power conversion circuit and a backup power source without momentary interruption.

[Conventional technology]

Figure 4 shows, for example, the publication [Electric Power and Railway JVoL1.2
7. Kan 10. It is a block diagram of the conventional AC uninterruptible power supply system shown in pages 26 to 28 (published by the Railway Electrification Association).

In the figure, 1 is a power conversion circuit (hereinafter referred to as an inverter) that serves as a regular power source, 2 is a commercial power source that is a backup power source,
4 is a semiconductor AC switch (SIRISK switch) provided in the main power supply path A, 5 is a semiconductor AC switch (SIRISK switch) provided in the bypass power supply path B, 6 is a load, 11 is a switching control power source, 12 is a switching control circuit, and both constitute a switching control device, and the switching control circuit 12 has a configuration as shown in FIG. In FIG. 5, 21 is a switching logic, 22 is a flip-flop, and 23 is an inverter gate.

Next, the operation of this device will be explained with reference to the time chart shown in FIG.

Normally, the switching control circuit 42 sends out a gate signal GA for driving the thyrisk switch 4, and power is supplied to the load 6 from the inverter 1 through the thyrisk switch 4. The switching control circuit 12 is the inverter 1
If the inverter 1 fails and its output is lost, the automatic switching condition is met (this time is T1), and the switching logic 21 sends a reset input to the flip-flop 22. give. As a result, the set output of the flip-flop 22 changes to the L level, so that the gate signal GA disappears and at the same time, the gate signal CB is generated and the thyristor switch 5 becomes conductive. Since the thyrisk switch 4 is turned off by natural commutation, if the load power factor is 1 due to the voltage phase at time T1, the switch 4 is turned off with an electrical angle of at most 180 degrees. In this way, instantaneous switching from the regular power source to the standby power source is realized.

[Problem that the invention seeks to solve]

In this way, in the conventional system, the switch 4 to the main power supply path
, the switch 5 of the bypass power supply path B is a semiconductor switch, and when the supply of gate signals to these switches is cut off, it turns off. When the output is lost, the gate signal GA disappears and the thyrisk switch 4 is turned off, and the gate signal CB is also not sent out, resulting in a problem that power supply to the load 6 is stopped.

The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide an uninterruptible power supply device that can supply power to a load from a regular power source without power outage even when the switching control power source is lost.

[Means to solve the problem]

In order to achieve the above object, the present invention employs a state-holding mechanical switch as the switch of the main power supply path, and the mechanical switch is configured to be opened and closed by a pulse signal having a predetermined duration.

[Effect]

In this invention, even if the switching control power source loses its output, the switch in the main power supply path continues to maintain the closed state before the loss of output, so a power outage does not occur.

[Embodiments of the invention]

FIG. 1 shows an embodiment of the present invention, in which the main power supply line A switch is a motor-operated no-fuse breaker.
This is different from the conventional case shown in FIG. 4 in that the opening/closing signal is a one-shot multi-pulse. This one-shot multi-pulse is created using one-shot multi pulses 24 and 25 shown in FIG.

Next, the operation of this device will be explained with reference to the time chart of FIG.

The no-fuse breaker 3 is closed by receiving a pulse (one-shot pulse) of a predetermined time duration from the one-shot multi 24 as an ON signal. Normally, the no-fuse breaker 3 is closed, and power is supplied to the load 6 from the inverter 1 through the no-fuse breaker 3.

When inverter 1 fails and its output is lost, backup power supply 2
When the automatic switching condition is established (this time is defined as TI), the switching logic 21 sends out the gate signal CB and drives the one-shot multi 25 at the same time. A pulse (one-shot pulse) of a predetermined time duration outputted by the one-shot multi 25 is supplied to the no-fuse breaker 3 as an OFF signal. The thyrisk switch 5 of the bypass power supply path B becomes conductive at the same time as it receives the gate signal CB, but
The no-fuse breaker 3 opens at time T3 after the off-operation delay time, and instantaneous switching from the inverter 1 to the standby power source 2 is realized.

In this embodiment, the switch of the main power supply path A is a state holding type switch 3, which maintains the closed state and the open state, respectively, even after the ON signal and OFF signal disappear. Maintain the previous closed circuit state,
After that, power supply from the inverter 1 to the load 6 continues.

In the above embodiment, a no-fuse breaker is used as the switch for the main power supply path A, but the switch may be of a state-holding type that operates with a one-shot pulse, such as a latch type electromagnetic contactor. .

〔Effect of the invention〕

As explained above, this invention uses a state-holding mechanical switch that opens and closes with a one-shot pulse for the main power supply path switch, so that even if the switching control power supply fails when power is supplied to the load from the regular power supply, the This has the advantage that load power supply can be continued and power outages due to failures of the switching control power source can be prevented.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a detailed block diagram of a switching control circuit in the above embodiment, and FIG. 3 is a time chart of signals of each part in the above embodiment.
Figure 4 is a block diagram showing a conventional uninterruptible power supply;
The figure is a detailed block diagram of the switching control circuit in the conventional example, and FIG. 6 is a time chart of signals of various parts in the conventional example. In the figure, 1 - inverter, 2 - commercial power supply, 3 -
Mechanical switch, 5--Sirisk switch, 11-
- Switching control power supply, 12-switching control circuit, A-main power supply path, B-bypass power supply path. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] A main feed line that supplies the output of the power conversion circuit to the load, a bypass feed line that feeds the power of the standby power supply to the load, a first switch provided on the main feed line, and a first switch provided on the bypass feed line. In the uninterruptible power supply system, the first switch is a state-holding mechanical switch, and the second switch is a state-holding mechanical switch. An uninterruptible power supply, which is a semiconductor switch, and wherein the first switch is controlled to open and close by a pulse signal having a predetermined duration.